#include<cstdio> //scanf()\printf() #include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int main(){ int n,i,s=0,a,q,b,sh,g; for(i=1;i<=n;i++) { cin>>a; q=a/1000; b=a/1000%10; sh=a%10; g=a%10; if(g-q-b-sh>0) s++; } return 0; }